Shelf unit



FIG. 1 is a front perspective view of a shelf unit showing my new design;

FIG 2 is a top elevation view thereof;

FIG. 3 is a bottom elevational view thereof;

FIG. 4 is a rear elevational view thereof; and,

FIG. 5 is an enlarged sectional view showing one of the corner posts of the shelf unit in greater detail. 

The ornamental design for a shelf unit, as shown. 